DSpace Collection:http://hdl.handle.net/123456789/35502017-09-26T21:49:55Z2017-09-26T21:49:55ZPersistent organochlorine pesticide residues in cocoa beans from Ghana, a concern for public healthOkoffo, E.DFosu-Mensah, B.Y.Gordon, C.http://hdl.handle.net/123456789/220062017-05-10T13:11:07Z2016-01-01T00:00:00ZTitle: Persistent organochlorine pesticide residues in cocoa beans from Ghana, a concern for public health
Authors: Okoffo, E.D; Fosu-Mensah, B.Y.; Gordon, C.
Abstract: Background: Residual levels of fifteen (15) organochlorine pesticides were determined in 32 cocoa bean samples
collected from sixteen (16) selected cocoa farms in the Dormaa West District of Ghana to assess the levels of
pesticides contamination.
Results: The results show that all cocoa bean samples analysed from the study area had one or more
organochlorine pesticide residues detected in them. The study revealed the presence of eight organochlorine
pesticide residues in the cocoa bean samples analysed at varying concentrations. The organochlorine pesticide
residues detected were aldrin (0.02–0.03 mg/kg), dieldrin (0.02–0.04 mg/kg), lindane (0.03–0.05 mg/kg), beta-HCH
(0.02–0.03 mg/kg), p,p'-DDE (0.02–0.03 mg/kg), p,p'-DDD (0.02–0.04 mg/kg), p,p’-DDT (0.04–0.05 mg/kg) and
methoxychlor (0.02–0.04 mg/kg). The most frequently found and abundant pesticide residue was the metabolite of
DDT (p,p’-DDT) which occurred in 62.5 % of the samples, followed by lindane (56.3 %) and then beta-HCH and
p,p’-DDD occurring in 50 % of the samples. None of the detected pesticide mean residues recorded from the
various study sites exceeded their European Union (EU) Maximum Residue Limits (MRLs) for cocoa beans except
beta-HCH at Krakrom (S3).
Conclusion: The levels of organochlorine pesticide residues in the fermented dried cocoa beans analysed compared
to the European Union (EU) commission regulations on pesticide residues showed no health risks to consumers of
cocoa beans from Ghana and no threat to cocoa export to Europe. The occurrence of organochlorine pesticide
residues in the samples analysed could be due to their illegal use by farmers in the study area or due to their past use,
since these chemicals are prohibited from agricultural use in Ghana. There should be regular monitoring of pesticide
residues especially in cocoa beans to protect consumers from health related risks. There is a need to check and enforce
regulations on the use of banned/restricted and unapproved pesticides in cocoa production in Ghana.
Description: Article2016-01-01T00:00:00ZAssessment of organochlorine pesticide residues in soils and drinking water sources from cocoa farms in GhanaFosu‑Mensah, B.Y.Okoffo, E.D.Darko, G.Gordon, C.http://hdl.handle.net/123456789/219862017-05-10T13:09:27Z2016-01-01T00:00:00ZTitle: Assessment of organochlorine pesticide residues in soils and drinking water sources from cocoa farms in Ghana
Authors: Fosu‑Mensah, B.Y.; Okoffo, E.D.; Darko, G.; Gordon, C.
Abstract: Residues of organochlorine pesticides were determined in soils and drinking water sources in cocoa growing areas
in Ghana. Soil samples analysed showed the presence of four organochlorine pesticide residues namely lindane
(0.005–0.05 mg/kg), beta-HCH (<0.01–0.05 mg/kg), dieldrin (0.005–0.02 mg/kg), and p,p′-DDT (0.005–0.04 mg/kg),
with dieldrin occurring most frequently. Similarly, organochlorine pesticide residues detected in the water samples
were lindane (0.01–0.03 μg/l), alpha-endosulfan (0.01–0.03 μg/l), endosulfan-sulphate (0.01–0.04 μg/l), dieldrin
(0.01–0.03 μg/l) and p,p′-DDT (0.01–0.04 μg/l), with heptachlor occurring most frequently. The concentrations of
the detected organochlorine residues in the soil samples were below their respective US maximum residues limits
(MRLs) for agricultural soils, except for lindane recorded at Kwakuanya (S4) and beta-HCH recorded at Krakrom (S3)
and Kwakuanya (S4). Similarly, the organochlorine pesticide residues recorded in the water samples were below and
within their respective WHO MRLs for drinking water except for alpha-endosulfan at Diabaa (S2) and Kwakuanya (S4)
at distance 0–15 m and Kwakuanya (S4) at distance 16–30 m, endosulfan-sulfate at Nkrankwanta (S1) and Diabaa (S2)
at distance 0–15 m and heptachlor at Krakrom (S3) at distance 16–30 m which were above their WHO MRLs. The presence
of the banned organochlorine pesticide residues in soil and water samples from the study area indicates that
these chemicals are still being used, illegally, on some cocoa farms. Routine monitoring of pesticide residues in the
study area is necessary for the prevention, control and reduction of environmental pollution to minimize health risks
Description: Article2016-01-01T00:00:00ZOrganophosphorus pesticide residues in soils and drinking water sources from cocoa producing areas in GhanaFosu‑Mensah, B.Y.Okoffo, E.D.Darko, G.Gordon, C.http://hdl.handle.net/123456789/219782017-05-10T13:08:14Z2016-01-01T00:00:00ZTitle: Organophosphorus pesticide residues in soils and drinking water sources from cocoa producing areas in Ghana
Authors: Fosu‑Mensah, B.Y.; Okoffo, E.D.; Darko, G.; Gordon, C.
Abstract: Background: Pests and diseases are recognised as major factors responsible for the decline in cocoa yield in Ghana.
This has resulted in an increased use of pesticides to increase productivity. The regular application and indiscriminate
use of chemicals have been associated with unintended environmental and human health consequence. The
objective of this study was to determine levels of 13 organophosphorus pesticide residues in soils and drinking water
sources in and around cocoa farms in Brong Ahafo region of Ghana.
Methods: Organophosphorus pesticide residues were determined by the use of a high resolution Varian CP-3800
Gas Chromatograph equipped with pulse flame photometric detector (PFPD) in 32 soils and 64 drinking water samples
from 16 cocoa farms in the Dormaa West District of Ghana.
Results: Four organophosphorus residues were detected in the soil and water samples at varying concentrations.
The organophosphorus residues detected in soil samples were chlorpyrifos (0.01–0.04 mg/kg), profenofos
(0.02–0.04 mg/kg) and pirimiphos-methyl (0.01–0.04 mg/kg) while the organophosphorus residues recorded in the
water samples were chlorpyrifos (0.01–0.05 μg/L), diazinon (0.01–0.04 μg/L) and pirimiphos-methyl (0.01–0.03 μg/L).
The concentrations of organophosphorus pesticide residues in the soil samples analysed from the various sites were
generally below and within US MRLs for agricultural soils. However, mean concentrations of chlorpyrifos and pirimiphos-
methyl recorded at Nkrankwanta (S1) were found to be above their respective US MRLs for agricultural soils. The
trends of organophosphorus pesticide residues in the water samples analysed from the various distances to cocoa
farms decreased with increase in distance to cocoa farm (ranking; 0–15 > 16–30 > above 30 m). All organophosphorus
pesticide residues recorded in the water samples from the various sites within the various distances were below
and within their respective WHO MRLs for drinking water except chlorpyrifos at Diabaa (S2) and Kwakuanya (S4) at
distance 16–30 m and diazinon at Kwakuanya (S4) at a distance 0–15 m which exceeded their WHO MRLs. There were
no significant (p > 0.05) sites differences in mean values of pesticide residues detected in soils and water samples.
Conclusions: The presence of organophosphorus in the samples analysed was an indication of the use of the pesticides
by cocoa farmers in the study area to control pest and diseases. The pesticide residues in the soil poses danger
to soil organisms as well as contaminate surrounding water bodies through runoff and leaching. In addition, there is
the likelihood of translocation of these residues from the soil into the cocoa beans and other crops (like vegetables
that are commonly intercropped with cocoa) through the root system, thereby posing health risks to consumers.
Chlorpyrifos and diazinon concentrations in drinking water exceeded their respective WHO MRLs at some sampled
sites and may pose health hazard to farmers’ household and the communities
Description: Article2016-01-01T00:00:00ZApplication of the QuEChERS procedure and LC–MS/MS for the assessment of neonicotinoid insecticide residues in cocoa beans and shells Journal of Food Composition and AnalysisDankyi, E.Carboo, D.Gordon, C.Fomsgaard, I.S.http://hdl.handle.net/123456789/219772017-04-25T11:17:24Z2015-09-01T00:00:00ZTitle: Application of the QuEChERS procedure and LC–MS/MS for the assessment of neonicotinoid insecticide residues in cocoa beans and shells Journal of Food Composition and Analysis
Authors: Dankyi, E.; Carboo, D.; Gordon, C.; Fomsgaard, I.S.
Abstract: The Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) procedure was applied and validated for
the analysis of neonicotinoid insecticide residues in cocoa bean matrix with high fat and high pigments.
Samples employed in the study were fermented and dried beans obtained from major cocoa producing
regions in Ghana where neonicotinoids are extensively used. Shells covering the beans were removed
and analyzed separately to examine insecticide distribution. Analytes in both matrices were extracted in
acetonitrile with sodium acetate and magnesium sulfate salts, cleaned up using a sorbent mixture of
primary secondary amine (PSA), C18 and graphitized carbon black (GCB), and quantified using liquid
chromatography tandem mass spectrometry (LC–MS/MS). Average recoveries at four levels of
fortification ranged from 92 to 111% with relative standard deviation of 16% for all analytes. Limits
of quantification ranged from 3 to 10 mg/kg for all neonicotinoids. Imidacloprid was the most frequently
encountered neonicotinoid and was quantified in more than 10% of deshelled bean and 30% of cocoa shell
samples, with concentrations ranging from 11.5 to 35.6 mg/kg and 11.8 to 214 mg/kg in cocoa beans and
shells, respectively. The findings from this study suggest a need for greater efficiency in neonicotinoid
application, to avoid the build-up of these insecticides to unsafe levels in cocoa beans.
Description: Article2015-09-01T00:00:00Z